1. Field of the Invention
The present invention relates to an airbag system for a front passenger""s seat. This front passenger""s seat airbag system is arranged in an instrument panel to the front of the front passenger""s seat of a vehicle.
2. Description of Related Art
The front passenger""s seat airbag system of the prior art has the modes described below for the expansion of an airbag. Specifically, the airbag extrudes at first from the instrument panel. The airbag is then expanded towards the rear of the vehicle along, for example, a windshield which is sloped downwards towards its front.
However, the airbag of the front passenger""s seat air bag system may be desired to satisfy the following purpose, namely, to reduce the expansion rate of the airbag towards the passenger seated on the seat, i.e., the expansion rate towards the rear of the vehicle.
An object of the present invention is to provide a front passenger""s seat airbag system capable of reducing the expansion rate of an airbag toward the rear of the vehicle.
In order to achieve this object, according to a first embodiment of the invention, there is provided a front passenger""s seat airbag system of the top-mount type arranged in an instrument panel below a windshield, comprising:
a door arranged on the upper face of said instrument panel;
a case; and
an airbag housed and held in a folded state in said case and including a gas inlet port for injecting an inflating gas thereinto, so that said airbag is expanded, by injecting the inflating gas into said gas inlet ports, towards the rear of a vehicle along said windshield while opening said door,
wherein said airbag further includes a commutator cloth arranged to cover said gas inlet port and to close the two sides in the transverse direction of the vehicle, and to open the two sides in the longitudinal direction of the vehicle.
In order to achieve the above-specified object, according to a second embodiment of the invention, there is provided a front passenger""s seat airbag system arranged in an instrument panel, comprising:
a door arranged on the upper face of said instrument panel;
a case; and
an airbag housed and held in a folded state in said case and including: a gas inlet port for injecting an inflating gas thereinto; and a ceiling wall portion confronting said gas inlet port, so that said airbag is expanded by injecting the inflating gas into said gas inlet port towards the rear of a vehicle while opening said door,
wherein said airbag is housed in said case by folding said ceiling wall side of said airbag to closely approach said gas inlet port, subsequently by transversely folding the two edges perpendicular to the transverse direction to closely approach the vicinity of the center, and further by longitudinally folding the left and right edges to closely approach the vicinity of the center.
In order to achieve the above-specified object, according to a third embodiment of the invention, there is provided a front passenger""s seat airbag system arranged in an instrument panel, comprising:
a door arranged on the upper face of said instrument panel;
a case; and
an airbag housed and held in a folded state in said case and including: a gas inlet port for injecting an inflating gas thereinto; and a ceiling wall portion confronting said gas inlet port, so that said airbag is expanded by injecting the inflating gas into said gas inlet port towards the rear of a vehicle while opening said door,
wherein said airbag further includes a commutator cloth arranged to cover said gas inlet port,
wherein said airbag is housed in said case by folding said ceiling wall side of said airbag to closely approach said gas inlet port, subsequently by transversely folding the two edges perpendicular to the transverse direction to closely approach the vicinity of the center, and further by longitudinally folding the left and right edges to closely the vicinity of the center, and
wherein said commutator cloth is arranged to close the two sides in the transverse direction of the vehicle, and to open the two sides in the longitudinal direction of the vehicle.
In the front passenger""s seat airbag system of the top-mount type according to the first embodiment of the invention, the internal pressure rises when the inflating gas is injected into the airbag at the time of expansion of the airbag. Then, the airbag pushes to open the door which is arranged on the instrument panel, until the airbag extrudes out of the instrument panel.
At this expansion time of the airbag, the inflating gas that flows into the airbag is branched to flow forward and backward by the commutator cloth. This quickly expands the airbag in the longitudinal direction. At this time, the front side portion extrudes towards the rear of the vehicle along the windshield. Conversely, the rear side portion protrudes towards the rear of the vehicle along the upper face of the instrument panel.
Specifically, the front side portion at the beginning of expansion extrudes towards the rear of the vehicle along the windshield which is sloped downward to the front. Conversely, the rear side portion at the beginning of expansion extrudes towards the rear of the vehicle along the upper face of the instrument panel. As a result, the airbag is expanded towards the rear of the vehicle at such a vertically large angle so as to close the space between the inner side face of the windshield and the upper face side of the instrument panel.
In the front passenger""s seat airbag system according to the first embodiment of the invention, therefore, the airbag, having extruded from the instrument panel, moves towards the rear of the vehicle at a vertically large angle, i.e., with a wide surface having a large area at the portion toward the passenger. In this mode, the airbag is not expanded to extrude partially backwards. As a result, in the front passenger""s seat airbag system of the first embodiment, the expansion rate of the airbag towards the rear of the vehicle can be reduced to reduce the expansion rate of the airbag toward the passenger.
In the front passenger""s seat airbag system according to the second embodiment of the invention, the internal pressure of the airbag rises when the inflating gas flows at the expansion time of the airbag from the gas inlet port into the airbag. Then, the airbag pushes to open the door which is arranged on the instrument panel, until the airbag extrudes from the instrument panel.
At this time, the airbag, having extruded from the instrument panel, is expanded while being extended to the two sides of the transverse direction thereby to undo the longitudinal folding, and is then expanded while being extended to the two sides in the direction perpendicular to the transverse direction, thereby to undo the transverse folding.
Specifically, the airbag is extended at first to the two sides of the transverse direction without extruding towards the rear of the vehicle. That is, at first, the airbag is expanded towards the rear of the vehicle while undoing its longitudinal folding with its surface having an enlarged wide area.
In the front passenger""s seat airbag system of the second embodiment of the invention, therefore, the airbag having extruded from the instrument panel is expanded towards the rear of the vehicle with its portion on the front passenger""s side being given a surface having a wide area which is enlarged to the two sides in the transverse direction. In the front passenger""s seat airbag system of the second embodiment, too, the expansion rate of the airbag towards the rear of the vehicle can be reduced to reduce the expansion rate of the airbag towards the passenger.
Here, the front passenger""s seat airbag system according to the second embodiment of the invention should not be limited to the top-mount type, but may also be of the midway-mount type.
In the front passenger""s seat airbag system according to the third embodiment of the invention, the internal pressure of the airbag rises when the inflating gas flows at the expansion time of the airbag from the gas inlet port into the airbag. Then, the airbag pushes to open the door which is arranged on the instrument panel, until the airbag extrudes from the instrument panel.
Moreover, the airbag is expanded at first, after having extruded from the instrument panel, while being extended to the two sides of the transverse direction thereby to undo the longitudinal folding. Conversely, the inflating gas that flows into the airbag is branched by the commutator cloth to flow either forward and backward perpendicular to the transverse direction, or upward and downward. As a result, the airbag is quickly extended to the two sides in the direction perpendicular to the transverse direction by the commutator cloth.
In other words, the airbag is expanded towards the rear of the vehicle with a wide area which is extended in four directions, including not only the transverse directions but also the perpendicular directions to the transverse direction.
In the front passenger""s seat airbag system according to the third embodiment of the invention, therefore, the airbag having extruded from the instrument panel is expanded towards the rear of the vehicle with the portion on the front passenger""s side being given a wide area which is extended in four directions including the transverse directions and the perpendicular directions to the transverse direction. In the front passenger""s seat airbag system of the third embodiment, therefore, the expansion rate of the airbag towards the rear of the vehicle can be reduced to reduce the expansion rate of the airbag towards the passenger.
Here, the front passenger""s seat airbag system according to the third embodiment of the invention should not be limited to the top-mount type, but may be of the midway-mount type.